Influence of turmeric on the microbial characteristics, lipid oxidation and sensory properties of canned African catfish in tomato sauce stored at 25oC and 45oC

Abstract

The aim of the study was to investigate the preservative effect of turmeric paste on African catfish in tomato sauce with a view to producing ready-to-eat catfish and reduce the stress of processing. The microorganisms associated with the products were enumerated, isolated and identified, lipid oxidation was monitored, and the organoleptic properties were assessed. The microbial load ranged between 0.000 and 2.635 log cfu/g during storage. Bacillus subtilis and Bacillus coagulans were isolated and there was no presence of pathogenic microorganisms. The range of free fatty acid, peroxide and thiobarbituric acid values were 0.3 – 0.5% oleic acid, 0.00 – 0.07 meqO2/kg of sample and 0.00 – 4.69 mg MDA/g respectively. Addition of turmeric had no significant effect (p > 0.05) on the taste, texture, aroma, colour and overall acceptability of the canned African catfish in tomato sauce samples. This study therefore established that addition of 3% and 4% turmeric paste to African catfish was effective in limiting microbial growth and reducing hydrolytic rancidity without having negative effect on consumer acceptability.